Lens Substance Aspiration
Rupal H. Trivedi
M. Edward Wilson
Lens substance aspiration has probably received the least interest in the discussion of management of pediatric cataracts. Pediatric cataracts are generally soft and can be aspirated easily. However, our target should be not only to aspirate the lens substance, but to aspirate it thoroughly. If lens material is left behind, even if it clinically resembles a harmless strand or fiber, it may leave a large number of mitotically active cells.1,2 These cells have the potential to grow across the visual axis and cause the proliferative form of visual axis opacification (VAO). Since VAO is one of the most frequent and severe complications in pediatric cataract surgery, meticulous removal of lens substance is a crucial step in the management of pediatric cataracts. The best means of reducing the incidence of this complication is to remove as many of these cells as possible at the time of cataract removal.1,2 Amaya and colleagues recommend using the term phacoaspiration for children as in most eyes, the lens is not hard enough to require any phacoemulsification power.3 However, the cortex is often gummy and is occasionally difficult to aspirate.
SINGLE-PORT VERSUS BIMANUAL APPROACH
The lens substance can be aspirated through a single port or using a bimanual approach. Single-port irrigation/aspiration (I/A) is an awkward maneuver for subin-cisional cortex removal.4 The technique of bimanual I/A was developed to make cortical removal easier. The technique uses two separate cannulas inserted through two sideport incisions. Anterior chamber (AC) stability during bimanual I/A requires the irrigation system to have a flow resistance lower than that of the aspiration system, which can be accomplished by using cannulas with larger lumen diameters and shorter lengths.5 A J-shaped cannula also helps us to approach the subincisional cortex more easily.6 Pediatric eyes are especially appropriate candidates for bimanual I/A because
Separate irrigation and aspiration help to maintain the AC and decrease the fluctuation of the AC. This is especially advantageous in pediatric eyes with low scleral rigidity.
The bimanual approach helps to achieve thorough removal of lens substance (especially subincisional), which, again, is very crucial when performing pediatric cataract surgery.
MANUAL VERSUS AUTOMATED APPROACH
Pediatric cataracts can be aspirated using the manual or the automated approach. In automated removal, the I/A mode is selected on either a phacoemulsification machine or a vitrector machine.
